Impact of rare earth (RE³⁺ = La³⁺, Sm³⁺) substitution in the A site perovskite on the structural, and electrical properties of Ba(Zr_0.9Ti_0.1)O₃ ceramics

Abstract

Undoped Ba(Zr0.9Ti0.1)O3 and rare-earth-doped (Ba1−xRE2x/3)(Zr0.9Ti0.1)O3 (RE3+ = La3+, Sm3+) perovskite compounds were synthesized by the conventional solid-state reaction route.

Structural, electrical, and dielectric study of the influence of 3.4% lanthanide (Ln3+ = Sm3+ and La3+) insertion in the A-site of perovskite Ba0.95Ln0.034Ti0.99Zr0.01O3

“…In general, in this type of material, conduction is controlled by oxygen vacancies (OVs). The activation energy of a stoichiometric ABO 3 perovskite is about 2 eV, while the E a value is 1 eV for ABO 2.95 and 0.5 eV for ABO 2.90 , 58,87,88 from the activation energy values found and presented in the table in can confirm that oxygen vacancies (OVs) are responsible for the conduction mechanism in BZT, BSmZT and BLaZT ceramics and precisely single ionized oxygen vacancies of activation energy about (0.3–0.5 eV) are responsible for the conduction at the grain boundaries and for the grain conductivity controlled by double ionized oxygen vacancies of activation energy about (0.6–1.2 eV). 86,89,90 …”

“…56,77 The analysis of the conductivity spectra for the lanthanide-doped (Ln = Sm 3+ and La 3+ ) and undoped BZT compound shows two plateau regions corresponding to the grain (low frequency) and grain boundary (high frequency) contribution and a single power law is not sufficient to explain its conduction mechanism. Therefore, the conductivity behavior of these three systems (BZT, BSmZT and BLaZT) can be explained by the modified Jonscher power law, 58,70 given below. σ ( ω ) = σ ac + A 1 ω n 1 + A 2 ω n 2 where, σ ( ω ) represents the total conductivity, σ dc is the dc conductivity arise, A 1 ω n 1 and A 2 ω n 2 mean the charge carrier transport properties (polarons, electrons and ions) of the grain and the joined grain in the BZT, BSmZT and BLaZT ceramic, respectively.…”

“…This shift can be justified by the deference of the effective ionic radii for the coordination of lanthanide 12 ( R Sm 3+ = 1.24 Å and R La 3+ = 1.36 Å) and barium ( R Ba 2+ = 1.61 Å) according to Shannon 56. 58 …”

“…The increase in dielectric permittivity for lanthanide-doped compounds compared to non-doped ones is caused by the substitution of barium by lanthanides, the cuboctahedral groups [BaO 12 ] are substituted by the deformed cuboctahedral groups [LnO 12 ] this process can be obtained by the Krӧger–Vink notation described by the equation below : 58 …”

Assessment of Conductivity through Impedance Analysis of CuO:Ho2O3 Modified BaZr0.05Ti0.95O3

“…Recently, Bendahhou et al have studied the electrical properties of La 3+ doped BZT using complex impedance spectroscopy, conductivity, modulus formalism, and charge carriers activation energy were used to explain the microstructure-electrical property relationship. 14 Bhargavi et al have studied the composition induced dielectric and conductivity properties of Eu 2+ and Gd 3+ doped barium zirconium titanate ceramics. 15 Bhargavi has investigated the diffusivity in the Gd 3+ modified BZT by modified Curie-Weiss law.…”